The present invention relates to a housing of a bearing. More particularly, the invention relates to a pressure-compensating arrangement for a bearing housing equipped with a seal protecting the housing against lubrication oil leakage.
Very often, in the art of bearing housings, particularly those which are employed in the equipment used for manufacturing food stuffs, pharmaceutical or chemical products it is required to totally prevent any leakage of lubrication oil from ball and roller bearings. The difficulties in preventing of even very small amounts of lubrication from leaking from bearing housings are encountered in practice because oil particles spinning during operation produce an over pressure in air contained in the bearing housing; although this pressure is not too great it, however may cause penetration of lubrication oil even through very reliable seals.
Efforts have been made to solve the problem. A number of narrow ventilation openings in the upper part of the bearing housing have been suggested; this effort, however failed. If these openings have been made sufficiently narrow to prevent spray water for cleaning of the machine from entering the bearing housing these openings became blocked by lubrication oil particles spinning in the housing during operation. If these openings were rather large to avoid their clogging by the oil particles these openings in this case failed to prevent cleaning spray water from passing through them into the interior of the bearing housing; the relatively large openings were also unable to keep oil particles within the bearing housing. It is to be understood that in production of food stuffs and pharmaceutical products it is necessary to regularly clean and wash the equipment so that the size of the ventilation openings suggested in the art was rather important.
None of the conventional art, however has suggested pressure-compensating means which prevent leakage of the lubrication oil of the housing and at the same time prevent admission of spray cleaning water into the bearing housing.